BC pills (or any hormonal BC) split into 5 groups...
1) the group of people who feel better on them
2) the group of people who they don't effect at all - except as BC
3) the group of people who feel worse on them
then the other 2 can be attached to any of the above.
a) People for whom the hormones are damaging to their health
b) People for whom the hormones are aiding their health
Anyone can be a 1a or 1b, 2a or 2b, 3a or 3b. It's a "try it and see" sort of thing.
And no... nothing sans abstinence or a hysterectomy/ovoectomy is 100% effective. Women can get their tube tied, cauterized, and STILL end up pregnant. All methods of BC just lower the chances of getting pregnant. Some more than others. The lowest rate of pregnancy is actually from the copper IUD. But even then, it's possible. Just very very rare. Similar to getting preggers after getting your tubes tied. It happens. But not as often with either of those as with any other form of BC.
Personally, I got pregnant using BC pills, condoms, AND spermacide all together. ((I now use the copper IUD))
You have several choices for non-hormonal BC:
- Condoms + Spermacide
- Diaphragm + Spermacide
- Cervical Cap + Spermacide
- Copper IUD (paraguard)
- Natural Family Planning ((only do this one if you're okay with having another child... it has the HIGHEST failure rate of any kind of BC, including hormonal BC))